Here's a wonderful specimen of TOURMALINE on MICROCLINE from the famed gem pegmatite in Paprock, Nuristan Province, Afghanistan. Mineralogists tell us that the change in color results from the changing chemical composition of the fluids in the pocket over the time necessary for the crystal to grow - and this can take thousands or even millions of years! This is another of our great finds from the Tucson Gem, Rock and Mineral Show.